A nanotechnology treatment that is from bone marrow stem cells has reversed multiple sclerosis symptoms in mice and it could eventually be used to help humans, according to a new study done by the researchers from the University of California.

"Until now, stem cell therapies for autoimmune and neurodegenerative diseases have produced mixed results in clinical trials, partly because we don't know how the treatments work," said corresponding author Weian Zhao, an associate professor of pharmaceutical sciences and biomedical engineering who is affiliated with the Sue & Bill Gross Stem Cell Research Center. "This study helps unravel that mystery and paves the way for testing with human patients."

Sclerosis or multiple sclerosis is a disease of the brain and spinal cord, and it could potentially disable a patient. In multiple sclerosis, the immune system attacks the protective sheath that covers the nerve fibers and it causes communication problems between your brain and your body. Eventually, the disease can cause permanent damage or even deterioration of the nerves.

The symptoms of multiple sclerosis vary, and it depends on the amount of nerve damage. Some people with severe multiple sclerosis may lose the ability to walk on their own, or they may even lose the ability to walk at all. Others may experience long periods of remission without any new symptoms.

In experiments done in the past, intravenously injected stem cells or cells that are taken from the bone marrow and is activated with interferon gamma often got trapped in filter organs before reaching their target. The researchers of this study avoided that problem by extracting nano-sized particles called exosomes from the stem cells and injecting them into mice with multiple sclerosis.

The exosomes are loaded with neuroprotective RNA and protein molecules that are anti-inflammatory, so they were able to slip through the blood-spinal cord barrier. In addition to lost motor skill rejuvenation and decreasing the nerve damage, they normalize the immune systems of the subject, and it is something that conventional drugs can't do. More experiments are planned.

"This novel treatment will be tested on humans in early 2020, initially on people with Type 1 diabetes," said co-lead author Milad Riazifar, who worked on the study as a pharmacological sciences doctoral student in Zhao's lab and is currently helping prepare for a City of Hope clinical trial of the method. "If successful, it could pave the way for treating other autoimmune diseases, including multiple sclerosis."

Other UCI researchers involved were Egest J. Pone, Aude I. Segaliny, Laura L. McIntyre, Ashley Hamamoto, Erika N. Calle, Wenbin Liao, Victor Pham, Jayapriya Jayaraman, Jonathan R.T. Lakey, and Craig M. Walsh. Support was provided by the National Institutes of Health, a National Institute of Neurological Disorders and Stroke training grant, an Otto W. Shaler Scholarship and France's ARC Foundation for Cancer Research.